Integrated circuit security

ABSTRACT

Verifying a product is disclosed. An image of a self-assembly (SA) pattern on a substrate from a scanner is received. The SA pattern has been initially created using a block copolymer (BCP) which has been annealed on the substrate. Data from the SA pattern is stored in a computer system. The SA pattern data is associated with the product. The SA pattern is an information carrying security mark having a set of features with corresponding locations within the information carrying security mark which uniquely identify the product.

BACKGROUND OF THE INVENTION

This disclosure relates to integrated circuit devices, and morespecifically, to a method and structure to protect integrated circuitsused in semiconductor devices.

Circuit counterfeiting is a major loss of revenue and reputation forintegrated circuit manufacturers. A circuit design can be stolen byreverse engineering or other means such as access to mask sets andhacking into design databases. The stolen circuit design is thenmanufactured at a lower quality foundry and parts are sold as ifproduced by the original integrated circuit manufacturer. Lower gradeparts are used in critical electronic systems and cause dramaticfailures. It has been estimated that one percent of semiconductordevices are counterfeit units. With the move to IoT devices, with lesscomplexity in integrated circuits, circuit counterfeiting is projectedto become a greater problem.

There has been recognition of the problem. The solutions to date havemostly been limited to the use of security markings, e.g., using specialsecurity ink on packages. With a special security ink, the manufacturerwill print some data such as a numeral, bar code or other marking.Typically, the markings will include data such as part number, serialnumber, data codes and logos. Various ink options are available such asvisible fluorescent inks, invisible fluorescent inks, UV invisible inks,IR invisible inks or UV long/short wave inks. A problem, however, isthat the printed data and ink are not unique and it is relatively easyto identify and reproduce a naming scheme or bar code identification.Those engaged in counterfeiting devices are becoming more skilled andwell financed and can gain access to the requisite ink and data forcounterfeiting purposes.

The present disclosure presents an advanced integrated circuit securityapproach to alleviate this problem.

BRIEF SUMMARY

According to this disclosure verifying a product is disclosed. In anembodiment of the invention, an image of a self-assembly (SA) pattern ona substrate from a scanner is received. The SA pattern has beeninitially created using a block copolymer (BCP) which has been annealedon the substrate. Data from the SA pattern is stored in a computersystem. The SA pattern data is associated with the product. The SApattern is an information carrying security mark having a set offeatures with corresponding locations within the information carryingsecurity mark which uniquely identify the product.

The foregoing has outlined some of the more pertinent features of thedisclosed subject matter. These features should be construed to bemerely illustrative. Many other beneficial results can be attained byapplying the disclosed subject matter in a different manner or bymodifying the invention as will be described.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present invention and theadvantages thereof, reference is now made to the following descriptionstaken in conjunction with the accompanying drawings which are notnecessarily drawing to scale, and in which:

FIG. 1 is a representation of a self-assembly (SA) pattern on asubstrate according to a first embodiment of the invention;

FIG. 2 is a flow diagram for using an SA process to mark an integratedcircuit according to a first embodiment of the invention;

FIG. 3 is a flow diagram for using an SA process to mark an integratedcircuit according to a second embodiment of the invention;

FIG. 4 is a flow diagram for using an SA process to mark an integratedcircuit according to a third embodiment of the invention;

FIGS. 5A and 5B are respectively top and cross-sectional diagramsdepicting an SA structure used for marking a chip package in anembodiment of the invention;

FIG. 6 is a top view diagram depicting an SA structure incorporated intoan integrated circuit chip in an embodiment of the invention;

FIG. 7 is a perspective view diagram depicting an SA structureincorporated into IC packing in an embodiment of the invention;

FIG. 8 is a flow diagram using an SA marked integrated circuit todetermine its authenticity in a verification operation;

FIG. 9 is a system diagram using an SA marked integrated circuit todetermine its authenticity in a verification operation; and

FIG. 10 is a block diagram of an exemplary data processing system isshown in which aspects of the illustrative embodiments may beimplemented.

DETAILED DESCRIPTION OF THE DRAWINGS

At a high level, embodiments of the invention increase security througha unique self-assembly (SA) pattern or “fingerprint” that is createdonto selected chips, chip locations and processing layers. An unguidedSA process is used to generate random and unique patterns which theinvention uses for integrated chip security. Once created, the unique SApatterns are captured, analyzed, transformed and enlarged in embodimentsof the invention. The enlarged versions of the SA patterns allow easiercustomer verification. In embodiments of the invention, rather thanverifying against an entire image of the SA pattern, a set of featuresand feature locations are used to efficiently store and recognize eachunique pattern. Embodiments of the invention utilize SA patternsattached to chips or packaging during manufacturing.

Embodiments will be explained below with reference to the accompanyingdrawings.

FIG. 1 is a top view diagram depicting a self-assembly (SA) patternaccording to a first embodiment of the invention. An alternate term usedin the specification is unguided self-assembly (USA). Directedself-assembly (DSA), as used in semiconductor manufacturing, is a guidedprocess in which the formation of lines or other structures are guidedeither through chemical or graphoepitaxy techniques. In chemical orchemoepitaxy techniques, a chemically patterned surface with differentchemical properties in different areas is laid down on the substrate anda block copolymer (BCP) is applied. The chemical pattern induces the BCPto form a pattern which is then “annealed” using either a thermal orsolvent based process. A block copolymer is made up of two types ofchemically incompatible polymeric blocks which separate to formnanostructures. In graphoepitaxy techniques, permanent or temporarytopographical features are patterned on or into the substrate, e.g., byusing lithographic techniques, which are mimicked by the BCP onceannealed. DSA is used to create straight lines or other desired shapesin the integrated circuit. DSA is frequently employed at nanoscale tofabricate features smaller than the features made by conventionaloptical lithography.

If no guidance is provided, the directed self-assembly becomesself-assembly (or unguided SA) which results in substantially randompatterns. By “substantially random”, the inventors mean unpredictablepatterns, e.g., where features in the patterns have statistically randomlocations in the overall pattern. The inventors recognized that thesepatterns are complex and in some ways resemble human fingerprints.Further, in the inventors' experience, each of the patterns is unique ascompared to any other pattern. The patterns are thus “non-clonable” andimpossible to calculate as they utilize the inherent randomness of anunguided SA process

In some preferred embodiments of the invention, a block copolymer (BCP)material is used in as unguided SA process to create an identifying SApattern or “fingerprint”. In embodiments of the invention, a patternsuch as that shown in FIG. 1 is created using a self-assembly process.Because of its random qualities, each SA pattern is a unique“fingerprint” which is used by the invention to uniquely identify a chipor package on which the SA pattern is created. The pattern itself iscomprised of one of the polymers in the BCP, or is a transferred, etchedpattern of the SA pattern in an underlying material such as a metal or asemiconductor. Referring to FIG. 1, the black portion of the pattern isthe polymer which remains of the chip level, while the white portion ofthe pattern is where the second polymer was present before being removedby the BCP process. Or, in alternative embodiments, the black color ofthe pattern represents the material of the chip level which was underthe BCP pattern. The white portion is the etched pattern of the BCPpattern (i.e. etched into the material of the chip level and potentiallyinto a second underlying material to provide visual contrast) where thesecond polymer was removed prior to an etch step.

In preferred embodiments of the invention, the pattern is created in oneor more allocated layers of the semiconductor chip in one or moreallocated areas of the chip. In some embodiments of the invention, thechip is a normally functioning integrated circuit chip. In otherembodiments of the invention, the chip is a special purpose SA patternchip whose purpose is to identify the package in which it isincorporated, typically with other functional chips. If an SA pattern isetched into a dielectric layer, a metal deposition step followed bychemical-mechanical polishing may be utilized to generate final patternof alternating metal vs dielectric lines (looking top-down). This wouldonly be used for on-chip (not on-package) embodiments and haveadvantages in imaging due to material contrast between metal anddielectric portions. In embodiments in which the pattern is created incertain layers of the chip, preferably the layer would be in the layersnear the surface of the chip so that they can be detected and imagedmore easily.

In embodiments of the invention, a set of SA patterns are used toidentify a chip or a package in which chips are incorporated. MultipleSA patterns are used in a single chip in some embodiments. In otherembodiments, a single SA pattern is associated with each chip and theset of single SA patterns is associated with the package in which thechips are incorporated. In yet other embodiments, some of the chips haveSA patterns while others do not in a given package. In many preferredembodiments of the invention, the SA pattern created in a chip isreplicated on the package, possibly in an enlarged form to facilitateverification.

In some embodiments of the invention, the single or multiple“fingerprints” in every shippable chip are recorded before packaging andstored in a secure database owned by the manufacturer. In otherembodiments of the invention, the SA patterns in the one or more chipsincorporated into a particular package are recorded after packaging andstored in the secure database and associated with the package. In yetother embodiments of the invention, the image of an SA pattern createdon one chip is captured and then enlarged and reproduced on thepackaging or on a special purpose SA chip and then recorded and storedin the secure database. In an embodiment of the invention, the SAinformation is combined with other markings, e.g., model and serialnumbers, bar codes, date of manufacture, to identify the chip orpackage.

For customer validation, one or more chips or packages from a receivedbatch are sampled and its SA patterns are observed. The observed SApatterns are validated against a database owned by the manufacturer. Asmentioned elsewhere, in some preferred embodiments, a least one of a setof SA patterns is enlarged on the packaging for validation andverification purposes. In other embodiments, SEM or optical microscopyis used to verify the SA pattern according to the chip location and chiplevel on which the pattern is recorded in the database to be present.

Embodiments of the invention provide a system and a method for storageand validation of the fingerprint for compactness and speed.

The recognition of an SA pattern can rely on some of the techniques forencoding fingerprints as fingerprint algorithms are a well-known art.However, certain differences between SA patterns and human fingerprintsexist and can be accounted for in the recognition algorithm used byembodiments of the invention. In actual human fingerprints, most of thecomplexity of the human fingerprint pattern is concentrated towards thecenter of the fingerprint pattern. Also, the area of interest wherefeatures occur when compared to the feature pitch is much smaller in ahuman fingerprint than in an SA pattern. That is, generally speaking,there are fewer whorls in a human fingerprint as compared to features inan SA pattern in some preferred embodiments of the invention. Thus, thesame algorithm used to compact human fingerprint information is notequally efficient for an SA pattern recognition process.

In these embodiments, the “care points” of interest are not exactly thesame as those in the human fingerprint recognition process. Care pointsin human fingerprint recognition are based on innate humancharacteristics, including the defining locations of features such asarches, loops and whorls of the fingerprint. The field directions of thelines surrounding the care points are typically part of the informationstored for human fingerprint recognition. As the SA patterns are theresult of the chosen manufacturing process, and are typically morecomplex than a human fingerprint, different algorithms define whatfeatures distinguish respective SA patterns. In one embodiment of theinvention for example, the system stores only the center locations offeatures, but not field directions of lines surrounding the centerlocation as would be typical in a human fingerprint recognition process.Because there are more features in an SA pattern, storing and verifyingonly the center locations can distinguish between SA patterns in a moreefficient way than storing and verifying both center locations and fielddirections.

FIG. 2 is a flow diagram for using SA to mark an integrated circuitaccording to an embodiment of the invention. In this embodiment, an SApattern is printed on a chip substrate material such as silicon. In step201, the silicon chip is patterned with an SA process in wafer form.Once the SA pattern is made, and the remaining steps (if any) of theintegrated circuit processing are completed, the wafer is diced intoindividual chips in step 203. At least some of these chips have one ormore unique SA patterns. At this point, in some embodiments, the SApatterns and their locations on the chips are scanned, featuresextracted and recorded in the database, step 205. To scan the nanoscaleSA pattern, tools such as Scanning Electron Microscopy (SEM), ScanningIon Beam Microscope and nanoscale optical microscopy, both far-field andnear-field techniques, are used to scan the SA pattern in embodiments ofthe invention. A camera is used in some embodiments of the invention andthe image captured by the camera is analyzed for the SA patternfeatures.

As shown, in step 207, the process continues where the chip is coatedwith a polymer for protection. Depending on the opacity of the polymer,the scanning and recording step is performed after this step inalternative embodiments.

In step 209, the coated chip is glued or otherwise bonded on to a targetchip package. If multiple SA marked chips are incorporated into the samepackage, multiple recorded SA patterns from step 205 are associated withthe target chip package in some embodiments. In yet other embodiments,depending on the placement of the SA patterns relative to the packagingand orientation of the chip, the scanning and recording step could occurafter the assembly of the target chip package.

In preferred embodiments of the invention, the entire SA pattern is notstored in the database. Instead, an algorithm is used to pinpoint thelocation of features in the SA pattern so that the pattern can bedescribed in a compact, efficient way. The features, or “extractedminutiae”, can be categorized by feature type, e.g., as a line-end, afork or a short-line feature. Other types of features such as whorls,loops or arches may be selected in the particular embodiment. Theprocess of feature extraction can include smoothing filter, orientationfield estimation and ridge extraction steps. Bitwise image operationsare utilized to identify different minutiae in some embodiments. In apreferred embodiment, these minutiae are stored efficiently using asparse matrix representation. Embodiments of the invention use the inputfeature list to verify a chip or package against a SA pattern databaseusing an elastic string match utilizing an edit distance metric tocompare a stored feature and feature location with the scanned values.

Because of the much larger information content, i.e. number of features,in a SA pattern than a human fingerprint, a more concise way of storingdata is possible and preferred in a memory-limited system like IoTdevices. For example, in one embodiment of the invention, only a singletype of feature, e.g., a line end, is scanned, located and stored. Whena customer scans the chip for verification only that type of feature isused in the verification process. Alternatively, the customer can scanfor all types of features, but the manufacturer will only use the lineend features to verify the chip or package. Not informing the customerwhich feature is used improves the security of the verification, whileallowing the manufacturer to save storage space and processing time.Rotating the feature used on a periodic basis, e.g., line end onMondays, fork on Tuesdays, will further improve security while stillallowing the storage space and processing time. A single type of featurewould not normally be sufficient to identify a human fingerprint.However, as there are many more features in an SA pattern to choosefrom, it will be sufficient in embodiments of the invention topositively verify an SA pattern.

FIG. 3 is a flow diagram for using an SA process to mark an integratedcircuit according to a second embodiment of the invention. In thisembodiment, one or more SA patterns produced on the semiconductor chipare reproduced on the packaging. The process begins similarly to thatdepicted in FIG. 2; in step 301, the silicon chip is patterned with anSA process in wafer form. Once the SA pattern is made, and the remainingsteps of the integrated circuit processing are completed, the wafer isdiced into individual chips. At least some of these chips that have oneor more unique SA patterns are scanned in step 303 (either before orafter wafer dicing) to take an image of the SA pattern. The SA patternsand their chip locations (if recorded) are recorded in the database,step 305.

In step 307, the chip(s) is packaged according to the manufacturingprocess. For example, an opaque black plastic packaging is used in someembodiments. In step 309, the SA pattern is retrieved from the databaseand enlarged to make the SA pattern easier for the customer to scan onthe packaging in a verification process. In the form created on theoriginal chip, the SA pattern is very small, i.e. the features arenanometers wide, and required expensive imaging equipment to discern oneSA pattern from another. By enlarging the SA pattern, less expensiveequipment is needed by the customer to verify the authenticity of thepackage. The enlarged SA pattern as well as any other desired markingscan then be embossed onto the packaging by e-beam or laser beam, step311. Other desired markings include model and serial numbers, date codesand manufacturer logos in some embodiments of the invention. Otherembodiments of the invention use different marking techniques to createthe enlarged image on the package. In an alternative embodiment of theinvention, the enlarged pattern is the inverse of the SA pattern on thechip.

FIG. 4 is a flow diagram for using SA to mark an integrated circuitaccording to a third embodiment of the invention. In this embodiment,one or more SA patterns produced on a semiconductor chip are reproducedon other chips using lithography. Because the SA pattern is complex,portions of the original SA pattern can be reproduced and still maintaina unique partial pattern. So in some embodiments of the invention, aportion of the created SA pattern is enlarged on the packaging. Theprocess begins similarly to that depicted in FIGS. 2 and 3. In step 401,the silicon chip is patterned with an SA process. Once the SA pattern ismade, the original, unique SA pattern is scanned and features identifiedin step 403. The original unique SA pattern is recorded in the database,step 405, either in the full pattern form or in a set of features andtheir locations in the SA pattern.

The SA pattern, or a portion thereof, is then enlarged in step 407 toprovide easier authentication at the customer. The enlarged SA patternis then used to pattern other chips on a wafer using conventionallithography and etch processes in step 409. These chips are calledenlarged SA pattern chips. If a portion of the SA pattern is used in theenlarged SA pattern, in some embodiments, location information is storedin the database indicating where the portion is located within theentire pattern.

In some embodiments, the enlarged SA pattern chips are on the same waferas the original chip on which the SA pattern was originally fabricated;in other embodiments, they are on a different wafer. In embodiments ofthe invention where a portion of the original SA pattern is used, it ispossible to use other portions of the pattern for respective enlarged SApattern chips.

In embodiments of the invention, the original SA pattern is created on adummy, nonfunctional chip, and is solely used for producing the patternwhich is subsequently enlarged on the enlarged SA pattern chips. Inthese embodiments, the enlarged pattern does not represent an SA patternon a functional chip in the package. However, the inventors recognize inmany cases, the customer will be uninterested in verifying both theenlarged SA pattern and the original, nanoscale SA pattern.

In some embodiments, as part of the enlargement process, the patternsare digitally manipulated, e.g., to provide greater contrast, invertingthe image or cutting portions of the original pattern. Thesemanipulations are reflected in the data stored in the database so thatthe customer can identify the pattern. As part of the manipulation,registration marks can be added to the SA pattern to enable the customerto more quickly identify feature location in the verification process.

The types of materials chosen for patterning is dependent on theimplementation of the invention. In embodiments of the invention wherethe enlarged SA pattern chip is a functional chip or is fabricatedalongside functional chips, the materials chosen for the enlarged SApattern need to be compatible with the particular layer of the chip inwhich they are fabricated. In nonfunctional enlarged SA pattern chips,the primary criterion is to choose materials with a good contrast forthe verification step at the customer. Exemplary material layers withgood optical contrast for optical detection are dielectric (silicondioxide or nitride) vs. metal (Al or Cu). So the etch would through afirst layer, e.g., a metal layer, or reveal the second layer, e.g., adielectric layer, below.

Next, the wafer is diced into individual chips in step 411. Because thepattern is already known at the time of patterning, as it is based onthe original SA pattern, there is no need to take another scan andrecord the respective SA patterns of the individual chips, so long asthe order of the chips is retained during further handling. Thisembodiment is advantageous in a semiconductor process where thelithography and etch steps are used in the final process steps so the SApattern is easily seen for verification purposes. Using durablematerials eliminates the need for the protective layer, and can be usedin chips having a manufacturing process in which the process steps whichbuild the unguided SA pattern would be difficult or undesirable toimplement.

The process continues in step 413 where the SA patterned chips are gluedor bonded onto a target chip package. The SA pattern is associated withthe package in the database storage in some embodiments of theinvention. In alternative embodiments, the association of the SA patternwith a particular chip is sufficient for verification.

FIGS. 5A and 5B are respectively top and cross-sectional diagramsdepicting an SA structure used for marking a chip package in anembodiment of the invention. The SA marked chip 501 is glued orotherwise bonded onto a target chip package 503. Although for ease inillustration, the SA pattern is depicted as covering the entire chiparea, in some preferred embodiments, the SA pattern is produced only ondesignated areas of the chip 501. Although a single chip is shown in thefigure, in other embodiments, multiple SA marked chips can be placed onthe same package.

FIG. 6 is a top view diagram depicting an SA structure incorporated intoan integrated circuit target chip package in an embodiment of theinvention. In this embodiment, the SA pattern 601 is produced directlyon the target chip package 603 to be secured. As mentioned above, anenlarged SA pattern 603 is embossed, etched, patterned or otherwisecreated onto package directly so can be easily detected by opticaltools. The enlarged SA pattern can be based on one or more SA patternsmade on the integrated circuit chips (not shown) inside the package 603.

FIG. 7 is a perspective view diagram depicting an SA structureincorporated into IC packaging in an embodiment of the invention. Thisillustration shows an SA patterned chip 701 visible through a window 702in an IC package 703, e.g., similar to the openings in erasableprogrammable read-only memory (EPROM) packaging. In alternativeembodiments, an enlarged embossed, etched or e-beamed pattern is visiblethrough the top of package.

FIG. 8 is a flow diagram using an SA marked integrated circuit todetermine its authenticity in a verification operation. The illustratedprocess is merely exemplary and one skilled in the art would recognizethat many variations to the process are possible, the process steps maytake place in a different order, with additional or fewer steps taken inalternative embodiments and within the scope of the invention.

The process begins in step 801 where the customer registers with themanufacturer to receive the SA pattern data from the manufacturer. Asthe information is highly sensitive, and the manufacturer does not wantpirate foundries obtaining it, the inventors envision that a securityhandshake between the manufacturer and customer using PKI certificatesor similar security measures is part of the registration process. Asrepresented by step 803, the customer receives a chip shipment from themanufacturer containing chips and/or packaging which has been markedwith the SA pattern of the invention. The shipment can have order numberor customer number information useful to request and receive the SApattern data from the manufacturer. The packing information can containinstructions such as a unique URL and code for retrieving theinformation. Alternatively, more sophisticated means for retrieving theSA pattern data could be employed in an embodiment of the invention.

In step 805, the customer scans the first SA pattern, e.g., with anoptical scanner like those used for bar codes or QR codes. A camera isused in alternative embodiments. The level of detail of the verificationprocess is left up to customer preference in preferred embodiments. Ifthe parts are shipped directly from the manufacturer and the customerhas reason to believe that there has been no tampering, a spot check ofa few randomly selected chip package will suffice. If, however, theparts come via a third party distributor or there is reason to doubttheir provenance, a more extensive scan and verification process isundertaken, possibly scanning each chip or package. The scan can alsoinclude both the enlarged SA patterns and at least some of the originalSA patterns on the chips themselves. Where more extensive verificationis undertaken, the SA pattern information from the manufacturer willalso be more extensive, including the location of the chip in thepackage containing the original SA pattern, the location of the SApattern on the chip, the layer on which the SA pattern is to be foundand so forth.

In step 806, the SA pattern data is exchanged between the customer andthe manufacturer. In preferred embodiments of the invention, the SApatterns are stored in a compressed manner where the features, thefeature type and feature location are stored, rather than the entireimage. This is much more efficient for storage and transmission of thepattern information. In embodiments of the invention, the SA patterninformation is correlated to chip and/or package number, customerinformation. As mentioned elsewhere, the SA pattern data includes chiplocation and level information in embodiments of the invention to helpthe customer locate the SA pattern as well as identify counterfeit chipswhich include the SA pattern at incorrect locations on the chip orpackaging. The location of registration marks, if any, are also includedin embodiments of the invention.

In preferred embodiments, the SA pattern data is not transmitted to thecustomer. Instead, the customer scans the SA pattern and sends theresults, e.g., feature and feature location data, back to themanufacturer for verification. The manufacturer will respond back to thecustomer whether the SA pattern matches one in the batch of parts whichwas shipped to the customer, or whether it is a valid pattern for thatpart number. The inventors believe that for improved security, thecustomer should send the scanned SA pattern data to the manufacturer forverification rather than have the manufacturer transmit the SA patterndata to the customer to verify shipment of chips or packages. Otherwise,counterfeit manufacturers can also send counterfeit information tocustomer to check against. Serial numbers of chips are preferably sentto the manufacturer along with the read SA patterns. Without a serialnumber, checking against a large batch of chips may unduly tax themanufacturer resources dedicated to chip security.

However, in alternative embodiments, the SA pattern information can besent from the manufacturer to the customer so that the customer performsthe verification process.

In the illustrative embodiment, the scanned SA pattern data is receivedin a batch by the manufacturer, and the verification of the chip orpackage is carried out on an individual basis. In alternativeembodiments, the scanning could be performed batchwise and then theverification could likewise be performed batchwise. Variations on batchand individual processing are used in embodiments of the invention. Instep 807, the first scanned SA pattern is verified. In this embodiment,the client uses the enlarged SA pattern for verification as it is easierthan the scanning electron microscopy (or other expensive microscopy)which is required to identify features in the original pattern at thenanoscale. If desired, an optional step(s) of scanning and verifying theoriginal SA pattern at the chip level is carried out in step 809. Theverification steps entail matching the expected features and featurelocations from the manufacturer with the scanned data from the customer,step 811. If the scanned data does not match the manufacturer supplieddata, interested parties such as the customer and manufacturer arenotified, step 813.

If there are more SA patterns to be verified, step 815, the processreturns to step 807. In an alternative embodiment, in reaction to theidentification of an unverified pattern, more samples of the batch ofchips or packages are made than originally intended to identify theextent of the counterfeiting problem in the shipment of parts. If thereare no more patterns to be scanned, the verification process iscomplete, step 817.

FIG. 9 is a system diagram of a system which uses an SA markedintegrated circuit to determine its authenticity in a verificationoperation. In this embodiment, the manufacturer system 901 is connectedto the customer system 903 using the internet 905 via securecommunication protocols. The manufacturer system 901 includes the SApattern data 904, a transform/enlarge module 906, a customer database907 and a registration module 909. The SA pattern data 904 as describedabout contains image data, feature and feature location data correlatedwith chip and package identification data. The transform/enlarge module906 is used to make the enlarged image according to the transformationrules using the original SA pattern as a source. The enlarged image maybe a simple enlargement, or it may be a transform in which the image isinverted, lines clarified and/or registration marks added. In theseembodiments, the transform/enlarge module 906 would have computer codefor image inversion, line clarification and registration mark addition.The result of transform/enlarge operation is stored in the SA patterndata 904, together with feature and feature location data for theenlarged image.

A customer database 907 is used to determine the identities oflegitimate parties who can make requests for data access during theregistration process. Also, chip and package identification informationcan be stored and associated with the customer and shipment informationto forward the correct SA pattern data in response to a registeredcustomer request. As SA pattern data is returned by customers, thisinformation can also be used to track the manufactured chips throughdistribution channels. The registration module is used to register,authenticate and authorize legitimate customers of the manufacture foraccess to the SA pattern information.

Also shown attached to the manufacturing system 901 are scanner(s) 911and engraver(s) 913. The scanner 911 is used to image the original SApattern manufactured on the chip using the unguided SA process describedabove. The engraver 913 is a laser engraver in embodiments of theinvention, but other engravers or printers are used in alternativeembodiments of the invention. It is used to engrave an enlarged versionof the SA pattern on the chip or package surface.

In the illustrated embodiment, the customer system 903 containsregistration 921, received SA pattern data 923, scanned data 925 andverification 927 software modules stored customer system memory. Theregistration module 921 is used to register that customer with themanufacturer so that the SA pattern data may be obtained in someembodiments. As described above, in other embodiments of the invention,the registration module 921 is used to enable the customer to sendscanned SA pattern data to the manufacturer for verification. Thereceived SA pattern data store 923 is used to store the SA pattern datareceived from the manufacturer. The scanned data store 925 is used tostore the SA pattern data which the customer obtains from their scannedchips and packages. In embodiments of the invention, the two data storesare combined into a single database. The verification module 927 is usedto verify the chips and packages as belonging to the manufacturer. Theoperation of embodiments of the invention are described with referenceto FIG. 8. Also shown attached to the customer system 903 is scanner 929which is controlled by verification module 927 in some embodiments.Multiple scanners are used in embodiments (not pictured) either to speedthe verification operation, or to scan different types of SA patterns,e.g., original, enlarged.

With reference now to FIG. 10, a block diagram of an exemplary dataprocessing system is shown in which aspects of the illustrativeembodiments may be implemented. Data processing system 1000 is anexample of a computer, such as manufacturer system 901 or customersystem in FIG. 9, in which computer usable code or instructionsimplementing the processes for illustrative embodiments of thedisclosure may be located.

With reference now to FIG. 10, a block diagram of a data processingsystem is shown in which illustrative embodiments may be implemented.Data processing system 1000 is an example of a computer, in whichcomputer-usable program code or instructions implementing the processesmay be located for the illustrative embodiments. In this illustrativeexample, data processing system 1000 includes communications fabric1002, which provides communications between processor unit 1004, memory1006, persistent storage 1008, communications unit 1010, input/output(I/O) unit 1012, and display 1014.

Processor unit 1004 serves to execute instructions for software that maybe loaded into memory 1006. Processor unit 1004 may be a set of one ormore processors or may be a multi-processor core, depending on theparticular implementation. Further, processor unit 1004 may beimplemented using one or more heterogeneous processor systems in which amain processor is present with secondary processors on a single chip. Asanother illustrative example, processor unit 1004 may be a symmetricmulti-processor (SMP) system containing multiple processors of the sametype.

Memory 1006 and persistent storage 1008 are examples of storage devices.A storage device is any piece of hardware that is capable of storinginformation either on a temporary basis and/or a permanent basis. Memory1006, in these examples, may be, for example, a random access memory orany other suitable volatile or non-volatile storage device. Persistentstorage 1008 may take various forms depending on the particularimplementation. For example, persistent storage 1008 may contain one ormore components or devices. For example, persistent storage 1008 may bea hard drive, a flash memory, a rewritable optical disk, a rewritablemagnetic tape, or some combination of the above. The media used bypersistent storage 1008 also may be removable. For example, a removablehard drive may be used for persistent storage 1008.

Communications unit 1010, in these examples, provides for communicationswith other data processing systems or devices. In these examples,communications unit 1010 is a network interface card. Communicationsunit 1010 may provide communications through the use of either or bothphysical and wireless communications links.

Input/output unit 1012 allows for input and output of data with otherdevices that may be connected to data processing system 1000. Forexample, input/output unit 1012 may provide a connection for user inputthrough a keyboard and mouse. Further, input/output unit 1012 may sendoutput to a printer. Display 1014 provides a mechanism to displayinformation to a user.

Instructions for the operating system and applications or programs arelocated on persistent storage 1008. These instructions may be loadedinto memory 1006 for execution by processor unit 1004. The processes ofthe different embodiments may be performed by processor unit 1004 usingcomputer implemented instructions, which may be located in a memory,such as memory 1006. These instructions are referred to as program code,computer-usable program code, or computer-readable program code that maybe read and executed by a processor in processor unit 1004. The programcode in the different embodiments may be embodied on different physicalor tangible computer-readable media, such as memory 1006 or persistentstorage 1008.

Program code 1016 is located in a functional form on computer-readablemedia 1018 that is selectively removable and may be loaded onto ortransferred to data processing system 1000 for execution by processorunit 1004. Program code 1016 and computer-readable media 1018 formcomputer program product 1020 in these examples. In one example,computer-readable media 1018 may be in a tangible form, such as, forexample, an optical or magnetic disc that is inserted or placed into adrive or other device that is part of persistent storage 1008 fortransfer onto a storage device, such as a hard drive that is part ofpersistent storage 1008. In a tangible form, computer-readable media1018 also may take the form of a persistent storage, such as a harddrive, a thumb drive, or a flash memory that is connected to dataprocessing system 1000. The tangible form of computer-readable media1018 is also referred to as computer-recordable storage media. In someinstances, computer-recordable media 1018 may not be removable.

Alternatively, program code 1016 may be transferred to data processingsystem 1000 from computer-readable media 1018 through a communicationslink to communications unit 1010 and/or through a connection toinput/output unit 1012. The communications link and/or the connectionmay be physical or wireless in the illustrative examples. Thecomputer-readable media also may take the form of non-tangible media,such as communications links or wireless transmissions containing theprogram code. The different components illustrated for data processingsystem 1000 are not meant to provide architectural limitations to themanner in which different embodiments may be implemented. The differentillustrative embodiments may be implemented in a data processing systemincluding components in addition to or in place of those illustrated fordata processing system 1000. Other components shown in FIG. 10 can bevaried from the illustrative examples shown. As one example, a storagedevice in data processing system 1000 is any hardware apparatus that maystore data. Memory 1006, persistent storage 1008, and computer-readablemedia 1018 are examples of storage devices in a tangible form.

In another example, a bus system may be used to implement communicationsfabric 1002 and may be comprised of one or more buses, such as a systembus or an input/output bus. Of course, the bus system may be implementedusing any suitable type of architecture that provides for a transfer ofdata between different components or devices attached to the bus system.Additionally, a communications unit may include one or more devices usedto transmit and receive data, such as a modem or a network adapter.Further, a memory may be, for example, memory 1006 or a cache such asfound in an interface and memory controller hub that may be present incommunications fabric 1002.

Computer program code for carrying out operations of the presentinvention may be written in any combination of one or more programminglanguages, including an object-oriented programming language such asJava™, Smalltalk, C++, C #, Objective-C, or the like, and conventionalprocedural programming languages such as Python or C. The program codemay execute entirely on the user's computer, partly on the user'scomputer, as a stand-alone software package, partly on the user'scomputer and partly on a remote computer, or entirely on the remotecomputer or server. In the latter scenario, the remote computer may beconnected to the user's computer through any type of network, includinga local area network (LAN) or a wide area network (WAN), or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider).

Those of ordinary skill in the art will appreciate that the hardware inFIG. 10 may vary depending on the implementation. Other internalhardware or peripheral devices, such as flash memory, equivalentnon-volatile memory, or optical disk drives and the like, may be used inaddition to or in place of the hardware depicted in FIG. 10. Also, theprocesses of the illustrative embodiments may be applied to amultiprocessor data processing system, other than the SMP systemmentioned previously, without departing from the spirit and scope of thedisclosed subject matter.

The present invention has many advantages over the prior art. Theembodiments of the invention increase security through a unique SApattern or “fingerprint” that is created onto selected chips, chiplocations and processing layers. An unguided SA process generates randomand unique patterns which the invention uses for integrated chipsecurity. The unique SA patterns are captured, analyzed, transformed andenlarged in embodiments of the invention. The enlarged versions of theSA patterns allow easier customer verification. In embodiments of theinvention, rather than verifying against an entire image of the SApattern, a set of features and feature locations are used to efficientlystore and recognize each unique pattern. Embodiments of the inventionutilize SA patterns are attached to chips and/or packaging duringmanufacturing. Thus, a very clear and controlled attachment of anidentifying pattern to a chip is possible.

While only one or a limited number of features are illustrated in thedrawings, those ordinarily skilled in the art would understand that manydifferent types of features could be simultaneously formed with theembodiment herein and the drawings are intended to show simultaneousformation of multiple different types of features. However, the drawingshave been simplified to only show a limited number of features forclarity and to allow the reader to more easily recognize the differentfeatures illustrated. This is not intended to limit the inventionbecause, as would be understood by those ordinarily skilled in the art,the invention is applicable to structures that include many of each typeof feature shown in the drawings.

While the above describes a particular order of operations performed bycertain embodiments of the invention, it should be understood that suchorder is exemplary, as alternative embodiments may perform theoperations in a different order, combine certain operations, overlapcertain operations, or the like. References in the specification to agiven embodiment indicate that the embodiment described may include aparticular feature, structure, or characteristic, but every embodimentmay not necessarily include the particular feature, structure, orcharacteristic.

In addition, terms such as “right”, “left”, “vertical”, “horizontal”,“top”, “bottom”, “upper”, “lower”, “under”, “below”, “underlying”,“over”, “overlying”, “parallel”, “perpendicular”, etc., used herein areunderstood to be relative locations as they are oriented and illustratedin the drawings (unless otherwise indicated). Terms such as “touching”,“on”, “in direct contact”, “abutting”, “directly adjacent to”, etc.,mean that at least one element physically contacts another element(without other elements separating the described elements).

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements in the claims below are intended toinclude any structure, material, or act for performing the function incombination with other claimed elements as specifically claimed. Thedescription of the present invention has been presented for purposes ofillustration and description, but is not intended to be exhaustive orlimited to the invention in the form disclosed. Many modifications andvariations will be apparent to those of ordinary skill in the artwithout departing from the scope and spirit of the invention. Theembodiment was chosen and described in order to best explain theprinciples of the invention and the practical application, and to enableothers of ordinary skill in the art to understand the invention forvarious embodiments with various modifications as are suited to theparticular use contemplated.

Having described our invention, what we now claim is as follows:
 1. Aproduct comprising: a substrate having a self-assembly (SA) pattern,wherein the SA pattern has been initially created using a blockcopolymer (BCP) which has been annealed on the substrate, wherein the SApattern is an information carrying security mark having a set offeatures with corresponding locations within the information carryingsecurity mark which uniquely identify the product.
 2. The product asrecited in claim 1, wherein the initial SA pattern has been created onan upper, physically observable layer.
 3. The product as recited inclaim 2, wherein the substrate is attached to the product so that theinitial SA pattern is a physically observable security feature.
 4. Theproduct as recited in claim 1, further comprising a package having anenlarged SA pattern, the enlarged SA pattern derived from the initial SApattern, wherein the substrate is attached to the package.
 5. Theproduct as recited in claim 4, wherein the package has an opening wherethe enlarged SA pattern is located and can be optically observed.
 6. Theproduct as recited in claim 1, further comprising a package on which thesubstrate has an enlarged SA pattern is attached, the enlarged SApattern derived from the initial SA pattern.
 7. A method formanufacturing a product comprising: creating a self-assembly (SA)pattern on a substrate, wherein the SA pattern has been initiallycreated using a block copolymer (BCP) which has been annealed on thesubstrate; scanning the SA pattern to capture an image of the SApattern; storing data from the SA pattern in a computer system, toproduce stored SA pattern data; and providing the SA pattern on theproduct; wherein the SA pattern is an information carrying security markhaving a set of features with corresponding locations within theinformation carrying security mark which uniquely identify the product.8. The method as recited in claim 7, wherein the SA pattern provided onthe product is the initial SA pattern created on an upper, physicallyobservable layer.
 9. The method as recited in claim 7, wherein the SApattern provided on the product uses the captured image of the SApattern and the method further comprises: generating an enlarged SApattern from the captured image of the SA pattern; and creating theenlarged SA pattern on the product.
 10. The method as recited in claim9, further comprising: providing a first layer and a second layer on thesubstrate, wherein the second layer is disposed on top of the firstlayer and is selected to provide an optical contrast to the first layer;providing a lithographic pattern on the second layer, the lithographicpattern a version of the enlarged SA pattern; and etching throughexposed portions of the second layer to create the enlarged SA patternon the substrate.
 11. The method as recited in claim 7, furthercomprising: storing a set of features and feature locations within thestored SA pattern data; associating the set of features and featurelocations with the product.
 12. The method as recited in claim 11,wherein the set of features are selected from the group consisting ofline end features, fork features and short-line features.
 13. The methodas recited in claim 7, further comprising: receiving a set of featuresand feature locations from a customer; verifying the received set offeatures and feature locations are as associated with the product. 14.The method as recited in claim 13, wherein the set of features andfeature locations are stored efficiently in the stored SA pattern datausing a sparse matrix representation and wherein the received set offeatures and feature locations are used to verify a customer productagainst an SA pattern database using an elastic string match utilizingan edit distance metric to compare the stored set of features andfeature locations with the received set of features and featurelocations.
 15. Apparatus, comprising: a processor; a computer memoryholding computer program instructions executed by the processor, thecomputer program instructions comprising: program code, operative toreceive an image of a self-assembly (SA) pattern on a substrate from ascanner, wherein the SA pattern has been initially created using a blockcopolymer (BCP) which has been annealed on the substrate; program code,operative to store data from the SA pattern in a computer system toproduce stored SA pattern data; and program code, operative to associatethe stored SA pattern data with a product; wherein the SA pattern is aninformation carrying security mark having a set of features withcorresponding locations within the information carrying security markwhich uniquely identify the product.
 16. The apparatus recited in claim15, further comprising: program code, operative to receiving an enlargedSA pattern generated from the SA pattern; program code, operative tostore SA pattern data about the enlarged SA pattern in the stored SApattern data in the computer memory; and program code, operative toassociate the stored SA pattern data about the enlarged SA pattern withthe product.
 17. The apparatus as recited in claim 16, wherein theprogram code, operative to generating an enlarged SA pattern from the SApattern further comprises: program code, operative to invert the SApattern image; program code, operative to clarify scanned lines from theSA pattern image; and program code, operative to add a registration markto the enlarged SA pattern.
 18. The apparatus as recited in claim 15,wherein the stored SA pattern data is a set of features and featurelocations from the SA image and the computer program instructionsfurther comprise: program code, operative to receive a set of featuresand feature locations from a customer; program code, operative to verifythe received set of features and feature locations as associated withthe product by matching the received set of features and featurelocations with the stored features and feature locations.
 19. Theapparatus as recited in claim 15, further comprising program code,operative to determine whether the customer is in a customer databaseand authorized to make requests.
 20. The apparatus as recited in claim15 further comprising program code operative to associate the stored SApattern data with model and serial numbers information.